Effect of traffic legislation on road traffic deaths in Ningbo, China

Purpose: Road safety is a major public health concern in China. However, the effectiveness of traffic laws in China is not known. We investigated the effect of traffic legislation on traffic deaths using data in Ningbo, China. Methods: We obtained traffic fatality data from 2002 to 2014 from the Ningbo Municipal Center for Disease Control and Prevention. An interrupted time series was used to look for change points in fatalities over time. We first used multiple change-point analysis to identify whether change points existed. Then, we checked if the identified change points corresponded to major changes in traffic legislation. Finally, we used a generalized additive model to examine the magnitude of those changes on fatalities. Results: A total of 12,412 traffic fatalities occurred in the study period. We detected two change points in traffic fatalities, which corresponded to the road safety law in 2004 and the Criminal Law Amendment criminalizing risky driving in 2011. The fatalities showed an 18.9% reduction (relative risk = 0.81, 95% confidence interval, 0.74–0.89) after the first change point and a further 19.2% reduction (relative risk = 0.80, 95% confidence interval, 0.74–0.89) after the second change point. Conclusions: Traffic legislation might improve road safety by spurring behavioral changes that reduce traffic deaths in China. These laws may provide a sound model for other similar countries.